1. Field of the Invention
The invention relates to a surface mounting device and its used support; in particular, to a surface mounting inductor and its used support.
2. Description of the Related Art
Generally, conventional surface mounting inductors are divided into several types. Referring to FIG. 1a and FIG. 1b, a surface mounting inductor 10 without a support is shown. Such surface mounting inductor 10 is provided with an iron core 11 and a coil 12. The coil 12 must be directly soldered to the bottom 111, as shown in FIG. 1c, of the iron core 11.
When the surface mounting inductor 10 is mounted on a printed circuit board (not shown), it cannot be isolated from the printed circuit board. Thus, circuits on the printed circuit board cannot pass through the bottom 111 of the iron core 11. As a result, the layout of the circuit requires additional space and the size of the whole printed circuit board increases.
Referring to FIG. 2a, FIG. 2b, FIG. 3a and FIG. 3b, other surface mounting inductors 20, 30 are shown. The surface mounting inductor 20 is provided with an iron core 21, a coil 22 and a support 23, and the surface mounting inductor 30 is provided with an iron core 31, a coil 32 and a support 33. The support 23 is provided with a pin 231, and the support 33 is provided with a pin 331. The coil 22 winds around the pin 231, and the coil 32 winds around the pin 331.
Electrodes of the surface mounting inductors 20, 30 are formed by L-shaped metal supports 23, 33 glued to the bottom of the iron core 21, 31. Since the fabricating process of the surface mounting inductors 20, 30 are simple, the manufacturing cost of the surface mounting inductors 20, 30 is lower than that of the surface mounting inductor 10. However, the surface mounting inductors 20, 30 have the same disadvantage as the surface mounting inductor 10. That is, when the surface mounting inductors 20, 30 are mounted on the printed circuit board, they cannot be isolated from the printed circuit board.
Referring to FIG. 4a and FIG. 4b, another surface mounting inductor 40 is shown. The surface mounting inductor 40 is provided with an iron core 41, a coil 42, a support 43, and two L-shaped metal parts 44. The coil 42 is soldered to the support 43. The L-shaped metal parts 44 are used as electrodes, and partially inserted into holes 45 of the support 43.
Referring to FIG. 5a and FIG. 5b, another surface mounting inductor 50 is shown. The surface mounting inductor 50 is provided with an iron core 51, a coil 52, a support 53, and two U-shaped metal parts 54. The support 53 is provided with an upper surface 531 and a flat bottom surface (not shown). The upper surface 531 is provided with a concave portion 531a with the iron core 51 disposed thereupon. The U-shaped metal parts 54 are used as electrodes, and fit with the circumference of the support 53. The coil 52 is soldered to the U-shaped metal parts 54. When the surface mounting inductor 50 is mounted on the printed circuit board, the bottom surfaces of the U-shaped metal parts 54 are in contact with the printed circuit board.
The surface mounting inductors 40, 50 have the following disadvantages:
1. Since the L-shaped metal parts 44 and the U-shaped metal parts 54 are disposed on the support 43, 53, the bottom surfaces of the supports 43, 53 are uneven; and
2. Since the supports 43, 53 are made of plastic, the strength of the supports 43, 53 is insufficient and the supports 43, 53 are easily damaged when the profile of the supports 43, 53 is thin. In contrast, when the thickness of the supports 43, 53 increases, the thickness of the whole surface mounting inductors 40, 50 also increases.
In order to address the disadvantages of the aforementioned surface mounting inductor, the invention provides a surface mounting inductor with an isolation support.
Another purpose of this invention is to provide a support for a surface mounting device having an inductive device.
Accordingly, the invention provides a support for modifying an inductive device to a surface mounting device. The inductive device is provided with a core and a coil, and the support includes an electric portion and an isolation portion. The electric portion, having a first surface and a second surface opposite to the first surface, is electrically coupled to the coil. The first surface of the electric portion is in contact with the core. The isolation portion is disposed on the second surface of the electric portion in a manner such that the isolation portion covers one part of the second surface of the electric portion. The isolation portion is flush with the other part of the second surface of the electric portion.
In a preferred embodiment, the electric portion is a metal plate with an L-shaped cross-section.
In another preferred embodiment, the electric portion includes two metal plates respectively having an L-shaped cross-section.
Furthermore, the metal plates are integrally formed.
In another preferred embodiment, the electric portion is a metal plate with a U-shaped cross-section.
In another preferred embodiment, the electric portion is provided with a plurality of pins for the coil winding thereon.
Furthermore, each of the pins is provided with a notch for leading the coil.
In another preferred embodiment, the electric portion is glued to the core.
In another preferred embodiment, the isolation portion is a paint layer coating on the one part of the second surface of the electric portion.
In another preferred embodiment, the isolation portion is a plastic film glued to the one part of the second surface of the electric portion.
In another preferred embodiment, this invention provides a surface mounting device. It includes a core, a coil, an electric portion and an isolation portion. The coil winds around the core. The electric portion, having a first surface and a second surface opposite to the first surface, is electrically coupled to the coil. The first surface of the electric portion is in contact with the core. The isolation portion is disposed on the second surface of the electric portion in a manner such that the isolation portion covers one part of the second surface of the electric portion. The isolation portion is flush with the other part of the second surface of the electric portion.